Recently I've encountered a problem, and quite frankly, of course it had to be one of those cases where nothing absolutely helps.
It started around a couple weeks ago, the system was getting random freezes, usually not long after startup, so I decided that maybe it's the time to do a clean reinstall of the system. Soon after which, I realized that my USB ports aren't working whenever I connect anything.
I tried resetting PRAM and SMC, multiple times, still nothing. The computer still freezes for a couple minutes (Touch Bar included), I can only move the cursor and click on stuff but everything is unresponsive until the freeze is gone.
Before you say that maybe my USB ports are fried or something, note that I have a Bootcamp partition, where everything works perfectly, USBs are fine, no freezes, everything works as it should, but not in MacOS. Even in Startup Manager I can move my external mouse, but as soon as system boots, it's unresponsive. If I keep using the system after one of it's freezes, chances are the connected mouse/keyboard will start working, as if it takes it a couple minutes to realize that something's connected.
It would've been much easier to assume that maybe the ports are bent or something but then in that case nothing would've worked in Bootcamp.
Specs: MBP 15' 2016, Mojave 10.14.6 (I tried updating to Catalina, no changes, so I rolled back since I don't like Catalina anyways)